TORONTO -- Tigers long reliever Luke Putkonen still has a chance to be ready to pitch by season's end, according to head athletic trainer Kevin Rand.

"He's throwing with that in mind," Rand said of Putkonen, out since mid-April with right elbow inflammation.

Putkonen threw off a mound for the first time in his rehab process Friday, delivering a 25-pitch bullpen session that included only fastballs.

"Right now he's in a bullpen progression program, which has him throwing bullpens for the next two weeks," Rand said. "If everything goes well there, hopefully we'll see him to start to try to throw to hitters and go from there."

The tricky part, if Putkonen progresses well, will be the final step to get him back to game action. At this timetable, he'd be readying for a rehab assignment just as Minor League seasons are wrapping up in late August and early September. So to get Putkonen ready, the Tigers would most likely have to set up simulated games for him.

Jason Beck is a reporter for MLB.com. Read Beck's Blog and follow him on Twitter @beckjason. This story was not subject to the approval of Major League Baseball or its clubs.